One must believe in the enjoyment of the grave, since the Prophet, salla-l-lahu ^alayhi wa sallam, conveyed this. Among the enjoyments include the widening of the grave to 70 by 70 cubits (dhira^) for the pious believer, as well as for those non-pious Muslims for whom Allah willed such a widened grave, like those who gained martyrdom but were not pious. Also, among the enjoyment of the grave is it being illuminated by a light that resembles the light of the full moon, and smelling the fragrance of Paradise. The Prophet, salla-l-lahu ^alayhi wa sallam, said:

“إذا قبر الميت أو الإنسان أتاه ملكان أسودان أزرقان يقال لأحدهما منكر وللآخر نكير فيقولان له: ما كنت تقول في هذا الرجل محمد، فهو قائل ما كان يقول، فإن كان مؤمناً قال: هو عبد الله ورسوله أشهد أن لا إله إلا الله وأشهد أن محمداً عبده ورسوله، فيقولان له إن كنا لنعلم أنك لتقول ذلك، ثم يفسح له في قبره سبعون ذراعاً في سبعين ذراعاً، وينور له فيه، فيقال له: نم فينام كنوم العروس الذي لا يوقظه إلا أحب أهله، حتى يبعثه الله من مضجعه ذلك”. رواه ابن حبان

“When the deceased – or a human – is buried, there come to him two blackish-bluish angels, one of whom is called Munkar and the other Nakir. They say: “What did you say about this man (known as) Muhammad?” – and he says what he used to say. If he was a believer, he would say: “He is the slave of Allah and His Messenger. I bear witness that there is no god but Allah and that Muhammad is His slave and Messenger.” They reply: “We knew that you would say that.” Then his grave is made spacious for him, seventy cubits by seventy, and it is illuminated for him. Then it is said to him: “Sleep,” and he sleeps like the bridegroom who will be woken by none but the dearest of his family to him, until Allah raises him from that resting place,” narrated by Ibn Hibban.